7 research outputs found
Metabolite-related dietary patterns and the development of islet autoimmunity
The role of diet in type 1 diabetes development is poorly understood. Metabolites, which reflect dietary response, may help elucidate this role. We explored metabolomics and lipidomics differences between 352 cases of islet autoimmunity (IA) and controls in the TEDDY (The Environmental Determinants of Diabetes in theYoung) study. We created dietary patterns reflecting pre-IA metabolite differences between groups and examined their association with IA. Secondary outcomes included IA cases positive for multiple autoantibodies (mAb+). The association of 853 plasma metabolites with outcomes was tested at seroconversion to IA, just prior to seroconversion, and during infancy. Key compounds in enriched metabolite sets were used to create dietary patterns reflecting metabolite composition, which were then tested for association with outcomes in the nested case-control subset and the full TEDDY cohort. Unsaturated phosphatidylcholines, sphingomyelins, phosphatidylethanolamines, glucosylceramides, and phospholipid ethers in infancy were inversely associated with mAb+ risk, while dicarboxylic acids were associated with an increased risk. An infancy dietary pattern representing higher levels of unsaturated phosphatidylcholines and phospholipid ethers, and lower sphingomyelins was protective for mAb+ in the nested case-control study only. Characterization of this high-risk infant metabolomics profile may help shape the future of early diagnosis or prevention efforts
The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance
INTRODUCTION
Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic.
RATIONALE
We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs).
RESULTS
Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants.
CONCLUSION
Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century
Prolonged pain research in mice: Trends in reference to the 3Rs
This literature review documents trends in the use of mice in prolonged pain research, defined herein as research that subjects mice to a source of pain for at least 14 days. The total amount of prolonged pain research on mice has increased dramatically in the past decade for the 3 pain categories examined: neuropathic, inflammatory, and chronic pain. There has also been a significant rise in the number of prolonged mouse pain studies as a proportion of all mouse studies and of all mouse pain studies. The use of transgenic mice has also risen significantly in prolonged pain research, though not as a proportion of all mice used in prolonged pain research. There has not been significant overall change in the number of mice being used per study for any of the 3 pain categories or for any of 3 common pain inducement models: chronic constriction injury, partial sciatic nerve ligation, and complete Freund’s adjuvant. Finally, although most authors referred to approval of experiments by an institutional nonhuman animal use committee, there were no references to the “3Rs” in a random selection of 55 papers examined. Given the proportionally high volume of mice used in invasive research and the gravity of studies that inflict lasting pain, these trends raise serious questions about whether the 3Rs principles of Replacement, Reduction, and Refinement are being appropriately implemented by researchers and institutions
Prolonged Pain Research in Mice: Trends in Reference to the 3Rs
This literature review documents trends in the use of mice in prolonged pain research, defined herein as research that subjects mice to a source of pain for at least 14 days. The total amount of prolonged pain research on mice has increased dramatically in the past decade for the 3 pain categories examined: neuropathic, inflammatory, and chronic pain. There has also been a significant rise in the number of prolonged mouse pain studies as a proportion of all mouse studies and of all mouse pain studies. The use of transgenic mice has also risen significantly in prolonged pain research, though not as a proportion of all mice used in prolonged pain research. There has not been significant overall change in the number of mice being used per study for any of the 3 pain categories or for any of 3 common pain inducement models: chronic constriction injury, partial sciatic nerve ligation, and complete Freund’s adjuvant. Finally, although most authors referred to approval of experiments by an institutional nonhuman animal use committee, there were no references to the “3Rs” in a random selection of 55 papers examined. Given the proportionally high volume of mice used in invasive research and the gravity of studies that inflict lasting pain, these trends raise serious questions about whether the 3Rs principles of Replacement, Reduction, and Refinement are being appropriately implemented by researchers and institutions